Chem test 4-5 Flashcards
The masses of the elements in a compound are always in the same ratio, this ratio is unique to each compound
Law of definite proportion
The symbol for the atomic number
Z
The symbol for the mass number
A
The symbol for the number of nuetrons
N
Isotope name and notation
carbon-12 and
A
X
Z
A whole number is equal to the sum of the protons and neutrons in the nucleus of a particular isotope of an element
Mass Number
atoms of the same element that have the same number of protons but different number of neutrons
Isotopes
A decimal number equal to the weighted average of the naturally occurring isotopes according to their percent abundance
Atomic mass
Protons Electrons and Neutrons of Silicon-28
14P 14E 14N
Protons Electrons and Neutrons of Calcium-44
20P 20E 24N
Who conceived the idea of atoms?
Democritus
The 3 subatomic particles in order of least mass to greatest
Electron, Proton, Neutron
The number of protons in each atom and its identity
Atomic Number
The sum of protons and neutrons in the nucleus of the atom
Mass number
Law of definite proportion
Each chemical has a unique composition by mass